Ozonizer

ABSTRACT

This invention relates to an ozonizer for generating ozone by causing a corona discharge to occur between electrodes oppositely arranged in air. An object of the ozonizer is to make the whole device compact and maintenance simple with reduction of the number of accessories. To this end, the ozonizer is characterized by that one of the electrodes comprises blades, the other electrode comprises a casing, and the blades and the casing form a blower. With this arrangement, it is not necessary to provide a particular blower for supplying fresh air continuously to the field of corona discharge and taking out ozone as it is produced.

BACKGROUND OF THE INVENTION

This invention relates to an ozonizer for generating ozone (O₃) bycausing a corona discharge to occur between electrodes oppositelyarranged in air.

As ozonizers of this type there have been developed various ozonizers inwhich a pair of electrodes are oppositely arranged in air, to which ahigh voltage is applied to induce a corona discharge therebetween whilecontinuously supplying air to the discharge field thereby to generateozone continuously.

In such devices, however, it is necessary that ozone produced in thefield of corona discharge should be continuously taken out of thedischarge field, and at the same time fresh air (oxygen) should besupplied to the discharge field. Therefore, the conventional ozonizersare provided with a blower, a pump or the like at the front or rear sideof the discharge field. Moreover, in the conventional ozonizers,especially in large ones, since the temperature of the electrodes risedue to the corona discharge, it is essential to provide a coolingdevice. This poses a problem that many accessories must be provided, sothat it is difficult to make the whole device compact and simplifymaintenance. An object of the invention is to solve such problemscompletely.

SUMMARY OF THE INVENTION

To attain the object this invention adopts the following arrangement.

The ozonizer of this invention is of the type that a corona discharge iscaused to occur between electrodes oppositely arranged in air, and ischaracterized by that one of the electrodes comprises blades, the otherelectrode comprises a casing, and the blades and the casing form ablower.

In this construction, by applying a high voltage between the bladeswhich form one electrode and the casing which forms the other electrode,it is possible to cause a corona discharge to take place between them.As the above-mentioned blades are driven by a motor in the same manneras in ordinary ventilators, air (oxygen) is drawn through an intake portand exhausted outside through a space formed between the blades and thecasing. At that time, oxygen in the air taken in passes through thefield of corona discharge, so that a part of the oxygen is changed toozone in this discharge field. The ozone produced in this manner iscontinuously exhausted outside in the above-mentioned flow.

This arrangement makes it unnecessary to provide an apparatus forcausing a corona discharge to occur and separately a blower forsupplying oxygen to the discharge field and taking out the ozonegenerated. As a result, the number of parts is reduced and the wholedevice can be made compact.

Moreover, since the gas positively flows in contact with the blades andthe casing which form the electrodes, thermal radiation from theelectrodes can be enhanced without difficulty.

Since the device of the invention is constructed as described above, itis possible to generate ozone efficiently, to make the whole devicesimple and compact, and to provide an ozonizer having a large capacitywithout the necessity of providing a cooling device having a highability.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view showing a cross section of oneembodiment of the invention;

FIG. 2 is a front view showing a cross section of the same embodiment;and

FIG. 3 is a perspective view showing another embodiment of theinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

One embodiment of the invention will be described below with referenceto the drawings.

The ozonizer has a fundamental structure of a Silocco type blowerprovided with an impeller 1 and a casing 2.

The impeller 1 is provided with a boss 11, circular side plates 12 andblades 13 mounted on the outer peripheral portions of the side plates atpredetermined intervals. The boss 11 is made of an insulating materialsuch as ABS resin or vinyl chloride, and a motor 3 has a rotary shaft 31connected to the boss 11. At least that side plate 12 which ispositioned opposite the motor 3 and provided with a window forventilation and the blades 13 are made of a material having a highelectrical conductivity such as stainless steel. The blades 13 functionas one of the electrodes. In other words, one of the electrodes iscomposed of the blades 13.

The casing 2 comprises an outer shell portion 21 and a circumferentialwall portion 22 enclosed within the outer shell portion 21. The outershell portion 21 is made of an insulating material such as ABS resin orvinyl chloride, and is provided with an intake port 23 near the centerof its end wall 21a opposite the above-mentioned motor 3 and an outletport 24 in the circumferential wall 21b thereof. The circumferentialwall portion 22 is fixed to the inner surface of the above-mentionedcircumferential wall 21b of the outer shell portion 21, and comprises astainless steel conductor 25 forming the other electrode and adielectric member 26 made of silicone rubber and attached to the innercircumferential wall of the conductor 25. In other words, in this devicethe other electrode forms a part of the casing 2.

A power supply 4 impresses a high voltage across the above-mentionedblades 13 and the above-mentioned conductor 25 which form theelectrodes. The power supply 4 is provided with a transformer 41 forproducing a potential difference, for example, 1000 V˜15000 V necessaryto generate a corona discharge between output terminals 41a and 41b, afirst connecting device 42 for electrically connecting the outputterminal 41a of the transformer 41 to the above-mentioned blades 13, anda second connecting device 43 for electrically connecting the otheroutput terminal 41b to the above-mentioned conductor 25. The inputterminals 41c and 41d of the above-mentioned transformer 41 areconnected to a suitable power supply 50. The first connecting device 42comprises a carbon-rod brush 44 inserted in the inner end portion of anaxial hole 21d formed in the central portion of the end wall 21c of theouter shell portion 21 of the casing 2 at the opposite side of the motorso that the brush 44 can project from and be retracted into the hole, astainless steel screw 45 screwed to the outer end portion of the hole,and a compression spring 46 of an electrically conductive materialinterposed between the screw 45 and the above-mentioned brush 44 so asto resiliently urge the above-mentioned brush 44 against the side plate12 of the above-mentioned impeller 1. The above-mentioned screw 45 isconnected to the terminal 41a of the above-mentioned transformer 41through an electrically conductive wire 47. The second connecting device43 comprises a stainless steel screw 48 screwed to the outer shellportion 21, with the inner end of the screw 48 contacting theabove-mentioned conductor 25, and the outer end thereof being connectedto the other output terminal 41b of the above-mentioned transformer 41through an electrically conductive wire 49.

With this arrangement, the blades 13 which form one of the electrodesare electrically connected to the output terminal 41a of the transformer41 through the side plate 12, the brush 44, the compression spring 46,the screw 45 and the electrically conductive wire 47. Thecircumferential wall portion 22 of the casing 2 which forms the otherelectrode is connected to the other terminal 41b of the above-mentionedtransformer 41 through the screw 48 and the electrically conductive wire49. Therefore, when the transformer 41 is connected to a power supply(not shown), a high voltage is impressed across the above-mentionedblades 13 and the above-mentioned circumferential wall portion 22, sothat a corona discharge is induced between the outer end surface 13a ofeach of the blades 13 which forms an electrode surface and the innercircumferential surface 26a of the above-mentioned dielectric member 26which forms a dielectric surface.

When the above-mentioned impeller 1 is driven by the motor 3 in the samemanner as in a conventional Silocco-type blower, fresh air (oxygen) istaken in through the intake port 23, and exhausted outside through theoutlet port 24 passing through a space formed between the blades 13 ofthe impeller 1 and the circumferential wall portion 22 of the casing 2.At this time, oxygen in the air taken in passes through the field ofcorona discharge 5, so that a part thereof is changed to ozone. Theozone generated in this manner is taken out of the field of coronadischarge 5 through the above-mentioned flow path, and continuouslyexhausted outside the casing 2 through the outlet port 24.

Thus, this arrangement eliminates the necessity of providing a devicefor causing corona discharges to be induced and a separate blower forsupplying oxygen to the field of corona discharge to generate ozone. Asa result, the number of parts is reduced, and an enhancement ofefficiency and reliability in manufacture can be achieved, and the wholedevice can be made compact.

Moreover, since air flows while positively contacting the blades 13 andthe casing 2 which form electrodes, radiation of heat from theelectrodes can be easily effected, so that it is possible to reduce thecooling ability of the cooling device without difficulty.

With this arrangement, since the blades 13 which form one of theelectrodes face at intervals the inner circumferential surface 26a ofthe dielectric member 26 which forms the dielectric surface of the otherelectrode, a higher corona discharge can be generated than if planeelectrodes were oppositely positioned. Since the positions of the blades13 relative to the inner circumferential surface 26a of the dielectricmember 26 are periodically changed, the electric charge stored on thewhole surface of the dielectric member 26 can be used. Therefore, it ispossible to enhance the efficiency of ozone generation in comparisonwith ozonizers with fixed electrodes.

The blower to which the invention may be applicable is not limited tothe Silocco type, but can be an axial flow type as shown in FIG. 3. Inthe apparatus shown in FIG. 3, one electrode is composed of blades 113of an impeller 101 of an axial flow type, and the other electrode iscomposed of a circumferential wall portion 122 of a casing 102. Thematerial of each part, means for supplying power to each electrode etc.may be selected as in the above-mentioned embodiment.

The ozonizer in accordance with the invention can be used as devices fordeodorization, sterilization, bleaching, etc. in various fields ofindustry.

We claim:
 1. An ozonizer for producing ozone from a corona dischargegenerated between spaced electrodes, said ozonizer comprising a blowerwherein said blower comprises an impeller with blades, each of saidblades having an outer end surface, and a casing having an inner wallportion circumferentially surrounding a major portion of a circumferenceof said impeller, said blades forming a first electrode and said innerwall portion forming a second electrode, whereby said corona dischargeis generated in a substantially uniform gap between the outer endsurfaces of said blades and an inner surface of said inner wall portion.2. The ozonizer according to claim 1, wherein said inner wall portionforming a second electrode comprises an outer conductor layer and aninner dielectric layer.
 3. The ozonizer according to claim 2, whereinsaid conductor layer is composed of stainless steel.
 4. The ozonizeraccording to claim 2, wherein said dielectric layer is composed ofsilicone rubber.
 5. The ozonizer according to claim 1, furthercomprising means for rotating the impeller.
 6. The ozonizer according toclaim 1, further comprising ozone outlet means formed within the casingand extending outwardly from a portion of the circumference of theimpeller which is not circumferentially surrounded by said inner wallportion.
 7. The ozonizer according to claim 1, wherein said inner wallportion circumferentially surrounds the entire circumference of theimpeller.